package network;

import java.io.IOException;
import java.net.*;
import java.util.Scanner;

public class UdpEchoClient {
    private DatagramSocket socket = null;
    private String serverIp;
    private int serverPort;

    public UdpEchoClient(String serverIp,int serverPort) throws SocketException {
        socket = new DatagramSocket();
         this.serverIp = serverIp;
         this.serverPort =  serverPort;
    }

    public void start() throws IOException {
        System.out.println("客户端启动！");
        Scanner scanner = new Scanner(System.in);
        while (true) {
            System.out.print("请输入要发送的请求：");
            String request = scanner.next();  //从控制台中读取用户输入
            //构造请求并发送  有数据 也要有目标
            DatagramPacket requestPacket = new DatagramPacket(request.getBytes(),0,request.getBytes().length, InetAddress.getByName(serverIp),serverPort);
            socket.send(requestPacket);  //发送请求
            //读取响应数据
            DatagramPacket responsePacket = new DatagramPacket(new byte[4096],4096);
            socket.receive(responsePacket);
            //显示响应到控制台
            String response = new String(responsePacket.getData(),0,responsePacket.getLength());
            System.out.println(response);
        }
    }

    public static void main(String[] args) throws IOException {
        UdpEchoClient client = new UdpEchoClient("127.0.0.1",9090);
        client.start();
    }
}
